This deer was simultaneously photographed by two trail cameras using an invisible flash - infrared night vision. Because both cameras were triggered at the same time giving the animal got a double dose of infrared.
This technology does not trigger a blinding flash like we know it - rather a light wave length that is not visible to the subject. This is known as electromagnetic radiation - or EMR - and happens to be a wavelength longer than that of visible light. As a consequence it is general invisible to the human and animal eye. One of the drawbacks is that night vision does result in an image reproduced only in varying shares of black and white. Considering it doesn't spook the critter that is a reasonable trade-off.
In case you are wondering about the dual camera set-up - I've had a Moultrie trail camera located here for possibly more than four years. Because it is close to water and sits at the confluence of three trails it is an excellent location. Some would suggest a hot location. When the Wisconsin DNR approved our hosting of a state camera for the Snapshot Wisconsin wildlife crowdsourcing program I located the DNR's Bushnell camera adjacent to the original camera.
Moultrie pic...
Bushnell pic...
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